Effect of Training LoadStructure on Purine Metabolism in Middle-Distance Runners.

MedLine Citation:

PMID:
21364483
Owner:
NLM
Status:
Publisher

Abstract/OtherAbstract:

There are no studies analyzing the effect of training loads on purine metabolism during long training periods. PURPOSE:: To evaluate the effect of training load changes and subsequent detraining on purine metabolism in middle-distance runners during a 1-year cycle. METHODS:: In four characteristic points of the training cycle, loads assigned to5 intensity zones, pre- and post-exercise plasma hypoxanthine (Hx) and uric acid (UA), and erythrocyte hypoxanthine-guanine phosphoribosyltransferase (HGPRT) activity were determined in 11 male middle-distance runners at national level, mean age 22.3±0.7 years, practicing competitive sport for 8.1±0.3 years, body mass 73.0±3.4 kg, body height 180±2.2 cm. RESULTS:: In competition phase (CP), training loads in aerobic compensation zone and aerobic threshold zone decreased by 65.4% and by 20.5%, respectively. At the same time, anaerobic training loads increased by 132.5% in maximal oxygen consumption zone and by74.6% in lactic acid tolerance zone. Post-exercise Hx decreased significantly in CPby 6.2 μmol·l and increased in transition phase (TP) by 17.4 μmol·l. Both pre- and post-exercise HGPRT activity increased significantly in CPby 9.3 nmol·mg·hand by 4.9 nmol·mg·h respectively, and decreased significantly in TPby 10.6 nmol·mg·h and by 12.0 nmol·mg·h, respectively. A significant UA increase by 54 μmol·l was revealed merely in TP. CONCLUSION:: The effect of anaerobic training on purine metabolism is significant despite of a very short total duration of anaerobic loads. Elevated pre-exercise HGPRT activity in CP suggests adaptation changes consisting in a "permanent readiness" for purine salvage. The detraining in TP leads to reverse adaptation changes. Probably, plasma Hx concentration and erythrocyte HGPRT activity may be considered as a useful measure of training status.

1Department of Athletics, University School of Physical Education, ul.DrogaDębińska7, 61-555Poznań, Poland 2Department of Physiology, University School of Physical Education, ul.KrólowejJadwigi 27/39, 61-871 Poznań, Poland.